Nine major users from the University of Wisconsin-Madison are applying for a Biomedical Research Support Shared Instrumentation Grant to purchase equipment for Protein Microsequencing and DNA Synthesizing Facility. We propose to establish a facility consisting of a) a gas-phase protein microsequencer to carry out sequential Edman degradation of proteins at a subnanomole scale, b) an HPLC for analyzing the resulting PTH-amino acid derivatives, and c) a DNA synthesizer for synthesizing defined DNA oligonucleotides. The ability to sequence subnanomole amounts of proteins and peptides will be invaluable in studies of difficult-to-purify proteins and in obtaining peptide sequence data to confirm DNA sequencing results. The ability to synthesize DNA oligo-nucleotides reproducibly and conveniently will allow us to carry out projects involving site-directed mutagenesis, synthesis of DNA regulatory signals, and design of artificial enzymes. A very important and exciting use, which requires both parts of the facility, is to clone genes for non-abundant proteins. Amino acid sequence information will be obtained and used to design DNA oligonucleotides that can be used as a hybridization probe to identify the gene of interest in gene libraries. Projects proposed here include the study of: 1) enzymes known to be deficient in human diseases; 2) enzymes central to regulating the expression of genetic information; 3) enzymes involved in metabolism of chemical carcinogens; 4) the structure and synthesis of small RNA viruses; 5) DNA sequences involved in regulating transcription termination; and 6) the structure and function of calmodulin, a key mediator of intracellular actions of calcium. This facility will give a large number of faculty who are conducting NIH-supported research access to a very powerful new technology that is presently not available at the University of Wisconsin. This technology will contribute significantly to the success of much of this research and is essential for maintaining the strength and continued progress of many research programs at this University.